Your wii u wont be able to handle both versions of Bayonetta(in terms of storage)

[Pillow]

only possible explanation is that the Xbox360 version was heavily compressed to fit on a single layered dvd (6.8GB max on Xbox360).

I think Lost Odyssey came on 4 discs which lowers the overall profits.

So Bayo1 Wii U is most likely uncompressed to have better audio/cut-scenes/textures.